This invention relates to a tool for rotationally adjusting threaded valve boxes.
In the typical urban environment a vast network of gas lines, oil lines, water lines, and the like run underneath the ground. Interspersed throughout the network is a number of valves for adjusting line pressure or for closing off portions of the lines for maintenance and other purposes. In order to access the valves, a metal pipe, typically called a valve box, is located at each valve and runs vertically to the surface. To open or close the valve, a long tool having a fitting that engages the valve is inserted down through the valve box so that the valve can be turned in the desired direction. In order to protect the valve, the valve box normally includes a protective cap that covers the vertical opening to prevent dirt and/or water from entering the valve box. The upper portion of the valve box typically includes a counterbore having a slightly angled or sloped sidewall that forms a seat for the protective cap. The sidewall of the protective cap is shaped to conform to the size and slope of the counterbore, which helps to prevent the protective cap from bouncing out when cars or other traffic runs over the valve box.
The gas and/or water lines are usually owned or maintained by utilities or municipalities and are normally routed along public rights of way, i.e. under the streets. Because the streets are periodically repaved or regraded, the height of the valve box must be adjusted in order to avoid having a bump or a hole where the valve box is located. Therefore, in place of a one piece valve box, municipalities normally use a two piece threaded valve box that can be threaded up or down so that the elevation of the protective cap matches the grade of the street. When a street is repaved, the contractor first scarifies the pavement in order to remove the top level of aggregate. Before scarifying, the upper portion of the two piece valve box must be lowered in order to avoid damage to the valve box, the protective cap, or the scarifying machine. After repaving is complete, the upper portion of the valve box must be raised so that the elevation of the top of the valve box matches the final grade of the street.
In the past, standard pipe wrenches and other tools have been used to adjust the valve box. These tools require that the street be excavated around the valve box and are, accordingly, very labor intensive and time consuming. Further, some tools used in the prior art fail to adequately grip the valve box, hence damaging the valve box or waste time by requiring re-adjustment of the tool.
The tools presently available require excavation around the valve box, and also require that the operator first attach the tool to the valve box, for example, by set screws before the valve box can be adjusted. While such prior art tools are being positioned and attached, the valve box is open and hence vulnerable to the entry of dirt and other contaminants.